<!doctype html>

<html>
<head>
  <link rel="shortcut icon" href="static/images/favicon.ico" type="image/x-icon">
  <title>collectablestorage.js (Closure Library API Documentation - JavaScript)</title>
  <link rel="stylesheet" href="static/css/base.css">
  <link rel="stylesheet" href="static/css/doc.css">
  <link rel="stylesheet" href="static/css/sidetree.css">
  <link rel="stylesheet" href="static/css/prettify.css">

  <script>
     var _staticFilePath = "static/";
     var _typeTreeName = "goog";
     var _fileTreeName = "Source";
  </script>

  <script src="static/js/doc.js">
  </script>


  <meta charset="utf8">
</head>

<body onload="grokdoc.onLoad();">

<div id="header">
  <div class="g-section g-tpl-50-50 g-split">
    <div class="g-unit g-first">
      <a id="logo" href="index.html">Closure Library API Documentation</a>
    </div>

    <div class="g-unit">
      <div class="g-c">
        <strong>Go to class or file:</strong>
        <input type="text" id="ac">
      </div>
    </div>
  </div>
</div>

<div class="clear"></div>

<h2><a href="closure_goog_storage_collectablestorage.js.html">collectablestorage.js</a></h2>

<pre class="prettyprint lang-js">
<a name="line1"></a>// Copyright 2011 The Closure Library Authors. All Rights Reserved.
<a name="line2"></a>//
<a name="line3"></a>// Licensed under the Apache License, Version 2.0 (the &quot;License&quot;);
<a name="line4"></a>// you may not use this file except in compliance with the License.
<a name="line5"></a>// You may obtain a copy of the License at
<a name="line6"></a>//
<a name="line7"></a>//      http://www.apache.org/licenses/LICENSE-2.0
<a name="line8"></a>//
<a name="line9"></a>// Unless required by applicable law or agreed to in writing, software
<a name="line10"></a>// distributed under the License is distributed on an &quot;AS-IS&quot; BASIS,
<a name="line11"></a>// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<a name="line12"></a>// See the License for the specific language governing permissions and
<a name="line13"></a>// limitations under the License.
<a name="line14"></a>
<a name="line15"></a>/**
<a name="line16"></a> * @fileoverview Provides a convenient API for data persistence with data
<a name="line17"></a> * expiration and user-initiated expired key collection.
<a name="line18"></a> *
<a name="line19"></a> */
<a name="line20"></a>
<a name="line21"></a>goog.provide(&#39;goog.storage.CollectableStorage&#39;);
<a name="line22"></a>
<a name="line23"></a>goog.require(&#39;goog.array&#39;);
<a name="line24"></a>goog.require(&#39;goog.asserts&#39;);
<a name="line25"></a>goog.require(&#39;goog.iter&#39;);
<a name="line26"></a>goog.require(&#39;goog.storage.ErrorCode&#39;);
<a name="line27"></a>goog.require(&#39;goog.storage.ExpiringStorage&#39;);
<a name="line28"></a>goog.require(&#39;goog.storage.RichStorage.Wrapper&#39;);
<a name="line29"></a>goog.require(&#39;goog.storage.mechanism.IterableMechanism&#39;);
<a name="line30"></a>
<a name="line31"></a>
<a name="line32"></a>
<a name="line33"></a>/**
<a name="line34"></a> * Provides a storage with expirning keys and a collection method.
<a name="line35"></a> *
<a name="line36"></a> * @param {!goog.storage.mechanism.IterableMechanism} mechanism The underlying
<a name="line37"></a> *     storage mechanism.
<a name="line38"></a> * @constructor
<a name="line39"></a> * @extends {goog.storage.ExpiringStorage}
<a name="line40"></a> */
<a name="line41"></a>goog.storage.CollectableStorage = function(mechanism) {
<a name="line42"></a>  goog.base(this, mechanism);
<a name="line43"></a>};
<a name="line44"></a>goog.inherits(goog.storage.CollectableStorage, goog.storage.ExpiringStorage);
<a name="line45"></a>
<a name="line46"></a>
<a name="line47"></a>/**
<a name="line48"></a> * Cleans up the storage by removing expired keys.
<a name="line49"></a> *
<a name="line50"></a> * @param {boolean=} opt_strict Also remove invalid keys.
<a name="line51"></a> */
<a name="line52"></a>goog.storage.CollectableStorage.prototype.collect = function(opt_strict) {
<a name="line53"></a>  var selfObj = this;
<a name="line54"></a>  var keysToRemove = [];
<a name="line55"></a>  goog.iter.forEach(this.mechanism.__iterator__(true), function(key) {
<a name="line56"></a>    // Get the wrapper.
<a name="line57"></a>    var wrapper;
<a name="line58"></a>    /** @preserveTry */
<a name="line59"></a>    try {
<a name="line60"></a>      wrapper = goog.storage.CollectableStorage.prototype.getWrapper.call(
<a name="line61"></a>          selfObj, key, true);
<a name="line62"></a>    } catch (ex) {
<a name="line63"></a>      if (ex == goog.storage.ErrorCode.INVALID_VALUE) {
<a name="line64"></a>        // Bad wrappers are removed in strict mode.
<a name="line65"></a>        if (opt_strict) {
<a name="line66"></a>          keysToRemove.push(key);
<a name="line67"></a>        }
<a name="line68"></a>        // Skip over bad wrappers and continue.
<a name="line69"></a>        return;
<a name="line70"></a>      }
<a name="line71"></a>      // Unknown error, escalate.
<a name="line72"></a>      throw ex;
<a name="line73"></a>    }
<a name="line74"></a>    goog.asserts.assert(wrapper);
<a name="line75"></a>    // Remove expired objects.
<a name="line76"></a>    if (goog.storage.ExpiringStorage.isExpired(wrapper)) {
<a name="line77"></a>      keysToRemove.push(key);
<a name="line78"></a>      // Continue with the next key.
<a name="line79"></a>      return;
<a name="line80"></a>    }
<a name="line81"></a>    // Objects which can&#39;t be decoded are removed in strict mode.
<a name="line82"></a>    if (opt_strict) {
<a name="line83"></a>      /** @preserveTry */
<a name="line84"></a>      try {
<a name="line85"></a>        goog.storage.RichStorage.Wrapper.unwrap(wrapper);
<a name="line86"></a>      } catch (ex) {
<a name="line87"></a>        if (ex == goog.storage.ErrorCode.INVALID_VALUE) {
<a name="line88"></a>          keysToRemove.push(key);
<a name="line89"></a>          // Skip over bad wrappers and continue.
<a name="line90"></a>          return;
<a name="line91"></a>        }
<a name="line92"></a>        // Unknown error, escalate.
<a name="line93"></a>        throw ex;
<a name="line94"></a>      }
<a name="line95"></a>    }
<a name="line96"></a>  });
<a name="line97"></a>  goog.array.forEach(keysToRemove, function(key) {
<a name="line98"></a>    goog.storage.CollectableStorage.prototype.remove.call(selfObj, key);
<a name="line99"></a>  });
<a name="line100"></a>};
</pre>


</body>
</html>
